/*$************************************************************************************************
**
** $Id$
**
** $Source: /cvs/ctree/LiteGO1/src/jar/com/polexis/lite/spatialschema/geometry/geometry/GenericSurfaceImpl.java,v $
**
** Copyright (C) 2003 Open GIS Consortium, Inc. All Rights Reserved. http://www.opengis.org/Legal/
**
*************************************************************************************************/
package org.geotoolkit.geometry.isoonjts.spatialschema.geometry.geometry;
import org.geotoolkit.geometry.isoonjts.spatialschema.geometry.AbstractJTSGeometry;
import org.opengis.geometry.DirectPosition;
import org.opengis.geometry.coordinate.GenericSurface;
/**
* Common interface for {@linkplain org.opengis.geometry.primitive.Surface surface} and
* {@linkplain org.opengis.geometry.primitive.SurfacePatch surface patch}. {@code Surface}
* and {@code SurfacePatch} represent sections of surface geometry,
* and therefore share a number of operation signatures.
*
* @author ISO/DIS 19107
* @author <A HREF="http://www.opengis.org">OpenGIS® consortium</A>
* @version 2.0
*
* @todo Why this interface is not defined in the primitive package, since the sub-interfaces
* ({@link org.opengis.geometry.primitive.Surface} and {@link org.opengis.geometry.primitive.SurfacePatch})
* belong to that package?
* @module
*/
public abstract class AbstractJTSGenericSurface extends AbstractJTSGeometry implements GenericSurface {
/**
* Returns a vector perpendicular to the {@code GenericSurface} at the
* {@linkplain DirectPosition direct position} passed, which must be on this
* {@code GenericSurface}. The upward normal always points upward in a
* manner consistent with the boundary. This means that the exterior boundary
* of the surface is counterclockwise when viewed from the side of the surface
* indicated by the {@code upNormal}. Interior boundaries are clockwise.
* The side of the surface indicated by the {@code upNormal} is referred
* to as the "top." The function "upNormal" shall be continuous and the length
* of the normal shall always be equal to 1.0.
*
* <blockquote><font size=2>
* <strong>NOTE:</strong> The upNormal along a boundary of a solid always points away from the
* solid. This is a slight semantics problem in dealing with voids within solids, where the
* upNormal (for sake of mathematical consistency) points into the center of the voided region,
* which linguistically can be considered the interior of the void. What the confusion is here
* is that the basic linguistic metaphors used in most languages for "interior of solid" and
* for "interior of container" use "inward" in inconsistent manners from a topological point
* of view. The void "in" rock is not inside the rock in the same manner as the solid material
* that makes up the substance of the rock. Nor is the coffee "in" the cup the same "in" as
* the ceramic glass "in" the cup. The use of these culturally derived metaphors may not be
* consistent across all languages, some of which may use different prepositions for these two
* different concepts. This specification uses the linguistically neutral concept of "interior"
* derived from mathematics (topology).
* </font></blockquote>
*
* @param point The point on this {@code GenericSurface} where to compute the upNormal.
* @return The upNormal unit vector.
*/
@Override
public abstract double[] getUpNormal(DirectPosition point);
/**
* Returns the sum of the lengths of all the boundary components of this
* {@code GenericSurface}. Since perimeter, like length, is an accumulation
* (integral) of distance, its return value shall be in a reference system appropriate
* for measuring distances.
*
* <blockquote><font size=2>
* <strong>NOTE:</strong> The perimeter is defined as the sum of the lengths of all boundary
* components. The length of a curve or of a collection of curves is always positive and
* non-zero (unless the curve is pathological). This means that holes in surfaces will
* contribute positively to the total perimeter.
* </font></blockquote>
*
* @return The perimeter.
*/
@Override
public abstract double getPerimeter();
/**
* Returns the area of this {@code GenericSurface}. The area of a 2-dimensional geometric
* object shall be a numeric measure of its surface area (in a square unit of distance). Since
* area is an accumulation (integral) of the product of two distances, its return value shall
* be in a unit of measure appropriate for measuring distances squared, such as meters squared
* (m<sup>2</sup>).
*
* <blockquote><font size=2>
* <strong>NOTE:</strong> Consistent with the definition of surface as a set of
* {@linkplain DirectPosition direct positions}, holes in the surfaces will not contribute to
* the total area. If the usual Green's Theorem (or more general Stokes' Theorem) integral is
* used, the integral around the holes in the surface are subtracted from the integral
* about the exterior of the surface patch.
* </font></blockquote>
*
* @return The area.
*
* @todo In UML diagram, the return type is {@code Area}.
*/
@Override
public abstract double getArea();
@Override
public String toString() {
return '[' + this.getClass().getName() + ']';
}
}